Coercivity enhancement of Dy-coated Nd-Fe-B flakes by crystallization

H. Fukunaga, Y. Sugimoto, M. Nakano, T. Yanai, S. Ohta, Masaru Itakura, Minoru Nishida

研究成果: ジャーナルへの寄稿記事

6 引用 (Scopus)

抄録

The coercivity of isotropic Dy-coated Nd-Fe-B flakes was enhanced by crystallization and simultaneous diffusion of Dy from their surfaces. Amorphous Dy-coated Nd-Fe-B flakes were crystallized by heating them to 923 K 2over a 2 min period followed by rapid cooling. During crystallization, the Dy on the surface diffused into the flakes. This low-temperature rapid annealing produced flakes with fine grains and the Dy diffusion enhanced their coercivity. The coercivity after crystallization increased with increasing Dy layer thickness, although the remanence decreased when the layer thickness exceeded 3 μm. Thick coatings of over 6 μm resulted in the formation of DyFe2, which degraded the magnetic properties of the crystallized flakes. Flakes with a 3-μm-thick coating exhibited excellent magnetic properties after annealing: They had a coercivity of 1880 kA/m and a remanence of 78 emu/g. This coercivity is approximately 500 kA/m higher than that of uncoated flakes, whereas the remanence is comparable to that of uncoated flakes.

元の言語英語
記事番号07A701
ジャーナルJournal of Applied Physics
109
発行部数7
DOI
出版物ステータス出版済み - 4 1 2011

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flakes
coercivity
crystallization
augmentation
remanence
magnetic properties
coatings
annealing
cooling
heating

All Science Journal Classification (ASJC) codes

  • Physics and Astronomy(all)

これを引用

Coercivity enhancement of Dy-coated Nd-Fe-B flakes by crystallization. / Fukunaga, H.; Sugimoto, Y.; Nakano, M.; Yanai, T.; Ohta, S.; Itakura, Masaru; Nishida, Minoru.

:: Journal of Applied Physics, 巻 109, 番号 7, 07A701, 01.04.2011.

研究成果: ジャーナルへの寄稿記事

Fukunaga, H. ; Sugimoto, Y. ; Nakano, M. ; Yanai, T. ; Ohta, S. ; Itakura, Masaru ; Nishida, Minoru. / Coercivity enhancement of Dy-coated Nd-Fe-B flakes by crystallization. :: Journal of Applied Physics. 2011 ; 巻 109, 番号 7.
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AU - Itakura, Masaru

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